System and method for concrete placement

ABSTRACT

A concrete finishing system may include a surface sensor, a depiction generator for generating a depiction of a profile of the concrete surface, and a display for displaying the depiction. The system may be used to perform a method of finishing concrete including arranging a surface sensor such that a work area for placement of the concrete is within a field of view of the surface sensor, capturing surface profile data of a surface of the concrete during placement or finishing of the concrete, generating a surface profile depiction based on the surface profile data, displaying the surface profile depiction, and informing personnel regarding a variation in height based on the depiction. The concrete slab formed with this process may include a floor flatness value above  35  and a surface free of ground areas and free of filled areas.

TECHNOLOGICAL FIELD

The present disclosure relates to concrete placement. More particularly,the present disclosure relates to a system and related method forsensing, scanning, or otherwise monitoring concrete slab placement andguiding concrete slab finishers during finishing to achieve very flatand/or level concrete surfaces. Still more particularly, the presentdisclosure relates to a 3D scanning system for monitoring one or morestages of concrete placement and finishing and a method of guiding theplacement and finishing process to arrive at a very flat and/or levelfloor.

BACKGROUND

The background description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventor, to the extent it is described in thisbackground section, as well as aspects of the description that may nototherwise qualify as prior art at the time of filing, are neitherexpressly nor impliedly admitted as prior art against the presentdisclosure.

Concrete slabs can include slab-on-grade, below grad, and elevatedslabs. Slab-on-grade slabs involve placing concrete on the ground with adesired thickness or elevation and finishing the top surface of theconcrete. Elevated slabs may involve placing concrete on formworksupported above the ground. In some cases, formwork may be temporaryformwork that is removed after the concrete is placed and after finalcure. In other cases, formwork may stay in place. For example,corrugated metal pans may be placed on top of supporting beams where thecorrugated metal is sufficiently strong to support the wet concrete andworker and equipment loading when the concrete is wet and becomes a partof the floor when the concrete is placed. In some cases, composite slabsmay be provided where steel studs are welded to the beams by securingthem to a top side of the corrugated metal and the welded connectionpenetrates the corrugated metal to secure the stud to the beam. Othertypes of elevated slabs may include post-tensioned slabs or systems orconcrete topping slabs. Still other types of elevated slabs may beprovided.

Whether a slab is a slab-on-grade or an elevated slab, the flatness andlevelness of the finished surface of the slab can affect a wide range ofthings relating to the construction of the structure and/or appearanceof the finished concrete. That is, for example, particular types offlooring may have relatively stringent tolerances for the underlyingslab flatness. For example, ceramic, porcelain, linoleum, laminate, orother types of tile may be sensitive to floor flatness. Installation oflater components may also be sensitive to floor flatness. For example,interior wall systems or partitions and, in particular, functioningdoors in those systems may be adversely affected if the slab is not flatenough. Exterior wall systems such as curtain wall systems and, inparticular, window mullions inside sliding glass doors, may beparticularly sensitive to slab flatness where the slab extends outbeyond the structure and is used to support the exterior wall systems.In the case of polished concrete, floor flatness and/or levelnesscriteria may be particularly stringent to provide a uniform appearance.

When a slab is poured and is insufficiently flat, a large amount ofconstruction time and cost may be incurred to correct the problem. Forexample, retroactive processes to address flatness problems may includeconcrete grinding to address areas that are overly high. Levelingcompounds may also be used to fill in areas that are too low. Moreover,where slabs are intended to be exposed, these grinding and levelingprocesses may adversely affect the resulting appearance of the concreteby changing the amount of aggregate exposure in some areas relative toother areas and/or by looking patched where the leveling compound ispresent. Nonetheless, common practices involve utilizing theseretroactive processes because it is often thought, particularly onelevated slabs, that specified floor flatness values are extremelydifficult to achieve during the placing and finishing process.

SUMMARY

The following presents a simplified summary of one or more embodimentsof the present disclosure in order to provide a basic understanding ofsuch embodiments. This summary is not an extensive overview of allcontemplated embodiments and is intended to neither identify key orcritical elements of all embodiments, nor delineate the scope of any orall embodiments.

In one or more examples, a concrete finishing system may include asurface sensor configured to capture surface profile data of a concretesurface. The surface sensor may be arranged such that a concrete workarea where concrete is being finished is within a field of view of thesurface sensor. The system may include a depiction generator configuredto generate a depiction of a surface profile of the concrete showing avariation in the flatness of the concrete surface. The system may alsoinclude a display configured to display the depiction.

In one or more examples, a method of finishing concrete may includearranging a surface sensor such that a work area for placement of theconcrete is within a field of view of the surface sensor. The method mayalso include capturing surface profile data of a surface of the concreteduring placement or finishing of the concrete. The method may alsoinclude generating a surface profile depiction based on the surfaceprofile data and displaying the surface profile depiction. The methodmay also include informing personnel regarding a variation in heightbased on the depiction.

In one or more examples, a concrete slab may have a floor flatness valueabove 35 and may include a surface free of ground areas and free offilled areas. The slab may be formed by a method including arranging asurface sensor such that a work area for placement of the concrete iswithin a field of view of the surface sensor. The method may alsoinclude capturing surface profile data of a surface of the concreteduring placement or finishing of the concrete. The method may alsoinclude generating a surface profile depiction based on the surfaceprofile data and displaying the surface profile depiction. The methodmay also include informing personnel regarding a variation in heightbased on the depiction.

While multiple embodiments are disclosed, still other embodiments of thepresent disclosure will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. As will be realized, thevarious embodiments of the present disclosure are capable ofmodifications in various obvious aspects, all without departing from thespirit and scope of the present disclosure. Accordingly, the drawingsand detailed description are to be regarded as illustrative in natureand not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter that is regarded as formingthe various embodiments of the present disclosure, it is believed thatthe invention will be better understood from the following descriptiontaken in conjunction with the accompanying Figures, in which:

FIG. 1 is a perspective view of a work area on a concrete project,according to one or more examples.

FIG. 2 is a perspective view of the work area with concrete placed andinitial forming of the concrete surface being performed and including asurface sensor, according to one or more examples.

FIG. 3 is a perspective view of the work area where the concrete isbeing finished with a bull float, according to one or more examples.

FIG. 4 is a perspective view of the work area after initial forming ofthe concrete surface and during capturing of surface profile data,according to one or more examples.

FIG. 5 is a view of a surface profile depiction captured after initialforming of the concrete surface, according to one or more examples.

FIG. 6A is a perspective view of a display displaying the depiction andincluding spot values, according to one or more examples.

FIG. 6B is a perspective view of a display displaying an image of thework area and including spot values, according to one or more examples.

FIG. 7 is a perspective view of a remediation operation based on thedepiction of FIG. 6A, according to one or more examples.

FIG. 8 is a perspective view of the surface sensor having been relocatedto a different vantage point on an opposite side of the work area,according to one or more examples.

FIG. 9 is a perspective view of the work area where the concrete surfaceis being further finished with a highway straight edge, according to oneor more examples.

FIG. 10 is a view of a surface profile depiction captured after furtherfinishing of the concrete surface, according to one or more examples.

FIG. 11 is a perspective view of the work area where machine finishingis being performed, according to one or more examples.

FIG. 12 is a perspective view of the work area where hand finishing isbeing performed, according to one or more examples.

FIG. 13 is a perspective view of the work area where further handfinishing correction is being performed in narrower areas, according toone or more examples.

FIG. 14 is a view of a surface profile depiction captured after machineand/or hand finishing of the concrete surface, according to one or moreexamples.

FIG. 15 is diagram depicting a series of floor flatness values,according to one or more examples.

FIG. 16 is a perspective view of the work area where floor flatness isbeing verified with a straight edge after placement, according to one ormore examples.

FIG. 17 is a perspective view of a slab edge outside of a column row onan outside edge of a structure, according to one or more examples.

FIG. 18 is a cross-sectional view of a concrete slab with a floorflatness of 25 after finishing and showing aggregate arrangement in theslab and relative to a floor flatness of 50, according to one or moreexamples.

FIG. 19 is a perspective view of a slab such as that of FIG. 18 aftergrinding operations, according to one or more examples.

FIG. 20 is a perspective view of a slab such as a slab having a floorflatness of 50 after finishing, according to one or more examples.

FIG. 21 is a diagram depicting a method of placing and finishing aconcrete slab, according to one or more examples.

DETAILED DESCRIPTION

The present disclosure, in one or more embodiments, relates to a systemand method for placing concrete. The system may include one or moretools, devices, and/or machines for placing, striking off, leveling, andsmoothing concrete. For purposes of monitoring and guiding the concreteplacement, the system may include a three-dimensional scanner or othermeasuring system that periodically captures surface profile data. Thesurface profile data may be displayed and/or communicated to concreteplacement personnel so they can take action to address surfaceirregularities or, in particular, flatness issues. The scanner maycapture surface profile data throughout the concrete placement processand varying levels of precision may be considered at the various stagesof concrete finishing. The system may provide a detailed on-the-flysurface profile never before available during concrete placement. Assuch, surface flatness and levelness or other finishing characteristicsmay be addressed during placement rather than after placement. This cansave considerable time and cost on a construction product and can alsoprovide an improved product with considerably flatter surface and a moreuniform appearance.

Turning now to FIG. 1 , a perspective view of a concrete project 50 isshown. As shown, the system 100 for placing concrete 54 may include oneor more concrete tools such as finishing tools including a screed orstrike off board 102 (FIG. 3 ), a bull float 104 (FIG. 3 ), a highwaystraight edge 106 (FIG. 9 ), a machine float and/or trowel 108 (FIG. 11), a hand float and/or trowel 110 (FIG. 12 ), level setting devices 112(FIG. 1 ), and other such tools and systems. Moreover, while not shown,concrete 54 may be delivered to a work area 52 on a concrete project 50via one or more concrete delivery trucks. Where the work area isaccessible by the trucks, the trucks may deliver the concrete 54directly to the project 50 via a chute on the back of the truck. Wherethe work area 52 is not accessible by the trucks (e.g., elevated floors,no roadway access, etc.), the trucks may deliver the concrete 54 to ahopper on a pump truck, which may pump the concrete 54 through a cranesupported hose to the work area 52. Alternative or additionally, thetrucks may deliver the concrete 54 to a hopper carried by a crane, to anauger, to a belt conveyor, or to another concrete conveyance systemarranged to transport the concrete 54 from the truck to the work area.One or more of these trucks and conveyance systems may also be part ofthe system described herein.

Referring now to FIG. 2 , the system may also include a surface sensor114. The surface sensor 114 may be configured to capture surface profiledata of the placed concrete 54 and produce a surface profile mapdepicting the surface profile. In one or more examples, the surfacesensor 114 may be a three-dimensional laser scanner. The laser scannermay be arranged on a tripod 116, for example, at or near a work area 52of a concrete project 50 allowing the scanner to capture surface profiledata of the placed concrete 54. The three-dimensional scanner mayinclude actuation features allowing the scanner to be activated to beginscanning and one or more indicators for signaling the operations of thescanner such as when the scanner actively scanning and/or when thescanner is complete. In one or more embodiments, the surface sensor 114may include a visual display 118 reflecting the area it is scanning andallowing for adjustment of the orientation and position of the scannerto capture the work area 52. While a three-dimensional laser scanner hasbeen provided other surface sensor devices may be used such as a lidarsensor, a series of digital cameras, or other devices capable ofcapturing and/or generating three-dimensional surface data of the placedconcrete 54. Moreover, and depending on the nature of the surface sensorused, the surface profile data may come in one or more forms. Forexample, in the case of a scanner or lidar sensor, for example, thesurface profile data may include point cloud data. In the case ofmultiple digital cameras, the surface profile data may include2-dimensional data that may be combined based on information about theframe of reference of the multiple cameras and overlapping image data,for example. Still other forms of surface profile data that defines theprofile of the surface may be captured and used.

The surface sensor 114 may include an onboard or remote depictiongenerator 120 for processing surface profile data and generating adepiction of the surface profile. For example, as shown in FIG. 5 , thedepiction generator 120 may generate a three-dimensional representationor depiction 122A of the surface profile that is suitable for displayingon a two-dimensional display. In one or more examples, the depiction122A may be a heat map showing degrees (e.g., areas A-E) or amounts ofdeviation from an otherwise flat surface. For example, particular colorsmay be used for ranges of deviation from flat. Alternatively oradditionally, the depiction may be a contour line map showing theboundaries between particular ranges of deviation from an otherwise flatfloor. In still other embodiments, the depiction may be athree-dimensional visual display. In any case, the depiction generator120 may be calibrated to adjust its level of precision depending on thestage of concrete placement it is being used to monitor. For example,when initially placing concrete and initially forming the concretesurface a screed or strike off board 102 may be used. With these toolsand at this stage of concrete placement, deviations from flat may beexpected to range from approximately ½ inch low to ½ inch high. However,when completing further finishing with a bull float 104 and/or a highwaystraight edge 106, deviations from flat may be expected to range fromapproximately ¼ inch low to ¼ inch high. Still further, when completingmachine floating and/or hand trowel operations, deviations from flat maybe expected to range from approximately ⅛ inch low to ⅛ inch high. Inview of this, the depiction generator 120 may have larger rangessuitable for depicting ½ inch deviations during strike off and may haveincreasingly smaller ranges as the concrete placement process continues.In one or more embodiments, the depiction generator 120 mayself-calibrate itself depending on the range of deviation is determinesis present from the surface profile data. The depiction generator 120may be a computing device that is a hardware component, a softwarecomponent, or a combination of hardware and software incorporated intothe surface sensor 114 as shown in FIG. 3 . In one or more otherembodiments, the depiction generator 120 may be part of a separatecomputing device that is in data communication with the surface sensor114.

The system may also include an onboard or remote display 118 fordisplaying one of several depictions 122A/B/C. For example, in one ormore embodiments, a separate computing device 124 such as a laptop,iPad, smartphone, or other computing device having a display 118 may beprovided. The computing device 124 may be in data communication with thesurface sensor 114 and may receive the depiction 122A/B/C (e.g., seeFIGS. 5, 10, and 14 ) from the surface sensor 114 and/or may receive theraw scanner data from the surface sensor 114 and may generate thedepictions 122A/B/C (e.g., see FIGS. 5, 10, and 14 ). That is, where thedepiction generator 120 is present on the separate computing device 124,the computing device 124 may receive raw data such as point cloud datafrom the surface sensor 114. In either case, the computing device 124may display the depiction 122A/B/C on the display 118 for review byonsite personnel. Alternatively or additionally, the display 118 may bepresent on the surface sensor 114, such as on a backside thereof, on anopenable/closeable screen, or another location on the surface sensor114, for example. Still other types of displays 118 may be provided.

In operation and use, the system 100 described above may be utilized toplace concrete and to monitor and guide the concrete placement to arriveat a concrete product with a suitably flat surface. With reference toFIG. 21 and supporting FIGS. 1-20 , a method 200 of concrete placementmay be provided. As shown in FIG. 21 and depicted in FIG. 1 , the methodmay include preparing the work area 202. For example, a ground surfacemay be prepared by grading, flattening, and/or filling with a basematerial. Elevated slab work areas may be prepared by placing orerecting concrete formwork in the form of temporary or permanentformwork. In addition, reinforcing bars may be placed in the work areaby arranging the reinforcing on supporting chairs, tying the reinforcingtogether, and otherwise securing the reinforcing to be encased inconcrete. In one or more embodiments, the reinforcing may extend in asingle direction or multiple directions and may include temperature andshrinkage reinforcement and/or structural reinforcement may be provided.Preparing the work area may also include setting level setting devices112. For example, as shown in FIG. 1 , boards may be secured to depthstands and adjusted to define a depth or thickness of concrete above theformwork. These level setting devices 112 may be used to guide pouringof the initial concrete to assist with arriving at a suitably thick andgenerally uniform slab of concrete 54.

With continued reference to FIG. 21 and as depicted in FIG. 2 , themethod may include setting up a monitoring system 204. In one or moreembodiments, setting up a monitoring system 204 may include placing asurface sensor 114 at or near the work area 52. The surface sensor 114may be arranged, oriented, and directed to place the work area 52 withina field of view of the surface sensor 114. In one or more embodiments,setting up the monitoring system may include placing the surface sensor114 adjacent to the work area 52 in a position to scan the work area 52from the side. The surface sensor 114 may be arranged on a tripod 116,for example, and the tripod 116 may be placed on the formwork or othersupporting surface generally adjacent the work area 52. The surfacesensor 114 may be adjusted to be directed generally horizontally, butslightly downward such that the anticipated concrete surface is within afield of view of the surface sensor 114. While this setting up processhas been described as being conducted before pouring of the concrete 54,it can be performed during or after pouring of the concrete 54 as notedby a comparison of FIGS. 1 and 2 .

As shown in FIG. 21 and with continued reference to FIGS. 1 and 2 , themethod may also include placing the concrete 206. As shown, this may beperformed using a hose 56 in fluid communication with a concrete pumptruck, for example. In other examples, hoppers, wheelbarrows, or otherconcrete conveyance means may be used. The concrete 54 may be pouredinto the work area 52 to the desired thickness. In one or more examples,a vibration mechanism may be used to increase the flowability of theconcrete 54 and to get the concrete 54 to flow under, over, and/oraround reinforcing bars and other items embedded in the concrete 54.

During and/or shortly after placing the concrete, the method may includeinitial forming of the concrete surface 208. This portion of the methodmay include striking off the concrete with a screed 102, for example, toarrive at a generally level top surface of the concrete as shown in FIG.2 . That is, a screed 102 in the form of a long, generally flat metalstraightedge or bar may be handled by two workers, for example, andlifted and dragged across the top of the concrete to scrape off and/orconsolidate the concrete to a generally uniform surface. In some cases,the screed 102 may be dragged and bounced to even out the surface and inother cases, the screed may be a vibratory screed 102 that may moresimply be dragged across the surface. In addition, smaller screeds onpoles or rods may be used to push and pull concrete and scrap off thetop surface, particularly at edges. Once the concrete is generally inits desired position with a rough, but generally uniform top surface, abull float may be used as shown in FIG. 3 , to begin the flatteningprocess of the surface of the concrete.

During or after the striking off process above and/or during or afterthe bull float process above, but before the further finishing discussedbelow, the method may include capturing a surface profile of theconcrete 210. Capturing a surface profile of the concrete may includeactuating the surface sensor 114 to capture three-dimensional surfaceprofile data. In one or more embodiments, this process may includescanning of the work area for a time ranging from approximately 30seconds to 2 minutes, or from 1 minute to 1 minute and 35 seconds, orfor a time of approximately 1 minute and 20 seconds. If efforts to takeimages/pictures while scanning, the time may be relatively longer suchas 2 minutes, 4 minutes, 7 minutes, or 15 minutes. Still other amountsof time may be provided for the process. In one or more embodiments, thesurface sensor 114 may remain stationary during this process.

The method may also include generating a surface profile depiction 212.This portion of the method may be performed by a depiction generator 120that may receive the surface profile data and generate athree-dimensional depiction 122A of the surface that is suitable for atwo-dimensional display. In one or more embodiments, and as shown inFIG. 5 , the depiction generator 120 may generate a heat map showinghigh and low areas and the degree of high and low areas based on coloredregions on the map. For example, red-hot areas may be substantially highareas and decreasing amounts of redness (e.g., orange and yellow) maydepict areas that are high, but not as high. Cyan colored areas may beareas that are close to a midpoint between the high and low areas (e.g.,the desired surface level) and low areas may be depicted with darkercolors such as dark blue or purple areas. Lesser amounts of purple orblue, such as green areas may be areas that are low, but not as low asthe darker areas, for example. Still other color profiles and uses ofcolor to depict high/low areas may be used. For example, the oppositemay be used where red-hot areas depict low areas and darker more purpleareas depict high spots. Still other approaches to the use of color toreflect relative heights of a surface may be used. Still otherapproaches to depicting high and low areas may include a depictionincluding contours or dividing lines between the areas. In one or moreembodiments, as shown in FIG. 6A, spot elevations may be providedthroughout the depiction 122A showing the elevation at particularlocations in the work area 52. In other examples, spot elevations may beprovided and overlaid on an image of the work area as shown in FIG. 6B

The method may also include displaying the surface profile depiction214. In one or more examples, this may include displaying the surfaceprofile on a handheld display 118 such as a laptop, iPad, or otherseparate display device. In one or more examples, displaying the surfaceprofile depiction may include displaying the depiction on a display ofthe surface sensor 114. Still other approaches to displaying thedepiction may be provided.

With continued reference to FIG. 21 , the method may also includeinforming placement and/or finishing personnel 216. That is, thedepiction may show high and low areas and may help to identifyparticularly problematic areas. In one or more examples, informingplacement and/or finishing personnel may include reviewing the depiction122A by personnel or having the personnel review the depiction 122A. Inother cases, informing placement and/or finishing personnel may includedirecting personnel to particular areas and informing them of thehigh/low nature of the area. It is to be appreciated that, at this stageof the process (e.g., during striking off), expectations for slabflatness may be to achieve a flatness within a selected tolerance, whichmay be a wider tolerance than the final slab flatness since furtherfinishing procedures may be performed. As such, in one or more examples,informing placement personnel may include informing placement personnelof areas that are outside the selected tolerance, where the tolerancemay range from, approximately 1 inch to -1 inch, or from approximately ¾inch to -¾ inch, or from approximately ½ inch to -½ inch, or fromapproximately ⅜ inch to -⅜ inch. For later finishing procedures, such asduring use of a bull float 104 and/or highway straight edge 106, thetolerance may be reduced (e.g., ⅜ to -⅜, or ¼ to -¼, or 3/16 to -3/16,inches) and for even later finishing procedures, such as during machinefloating/troweling or hand floating/troweling, the tolerance may befurther reduced (e.g., 3/16 to -3/16, or ⅛ to -⅛, or 1/16 to -1/16,inches).

As depicted in FIG. 7 , the method may also include remediating high andlow areas 218. For example, based on the informing step above, placementand/or finishing personnel may address high/low areas by removing/addingconcrete, respectively, to the high/low areas. FIG. 7 , for example,shows personnel addressing a particularly high area along a future walllocation.

In one or more examples, the method may also include repositioning thesurface sensor 220. That is, as shown in FIG. 8 , the surface sensor 114has been moved to an opposite side of the work area 52 and arranged atan elevated vantage point (e.g., a story above the work area). In one ormore examples, this may be performed to clear out of an area whereadditional concrete 54 is being placed and/or to provide a differentperspective on the concrete surface where, for example, some areassuffer from an obstructed view, for example. Still other bases forrepositioning the surface sensor may occur. The repositioning processmay include removing the surface sensor 114 from its position, moving itto a new position, and setting up the surface sensor 114 using the sameor similar steps as the method step of setting up the monitoring system204.

The method may also include further finishing of the concrete surface222. For example, as shown in FIG. 9 , the surface of the concrete maybe further finished using a highway straight edge 106, for example. Ahighway straight edge 106 may include a relatively wide blade with asmooth and flat bottom surface pivotally secured to the end of a longpole. The blade may be dragged along the surface of the concrete 54 byplacement or finishing personnel to smooth out the surface. The highwaystraight edge 106 may further flatten the surface of the concrete 54 andmay be used to create a surface that meets a higher flatness tolerancethan the earlier processes (e.g., strike off and bull float).

The method may include repeating several of the processes 224 describedabove during or after the process of further finishing the concrete, butbefore the process of machine or hand finishing discussed below. Thatis, for example, the steps of capturing a surface profile 210,generating a surface profile depiction 212, displaying the depiction214, informing placement and/or finishing personnel 216, and remediatinghigh/low areas may be repeated 218. However, the tolerance used at thisstage of the process may be slightly lower or tighter, as describedabove. As shown in the depiction of FIG. 10 ., the variance in thehigh/low regions may be reduced as compared to the depiction 122A ofFIG. 5 (e.g., areas A-C as compared to A-E) and the surface profiledepiction 122B may begin to look more uniform and/or with fewer regionsthat vary from the desired surface elevation or with regions that varyless from the desired surface elevation.

The method may also include machine finishing of the concrete surface226. For example, as shown in FIG. 11 , a walk-behind power float ortrowel 108 may be used. In one or more examples, a riding power float ortrowel may be used. In one or more examples, finishing personnel maywait for concrete to being to “set up” before engaging the concretesurface with a power float or trowel. In one or more examples, thiswaiting period may end when bleed water or moisture on the surface ofthe concrete has evaporated or otherwise cleared. Alternatively oradditionally, the end of the waiting period may be determined byassessing the amount of impression left by a footprint (e.g., ¼ inch orless). As shown in FIG. 11 , machine finishing of the concrete mayinclude operating a power pan float or trowel blades on the surface ofthe concrete. The power pan float or trowel blades may include severalspinning blades arranged in a fan-like formation. The blades may rotateunder power of a motor in a smoothing fashion and the power pan float ortrowel blades may be moved across the top surface of the concrete tofinish the surface of the concrete. In particular, a pan may be placedbelow the trowel blades in a first machine finishing process and the panmay then be removed. A second machine finishing process may includeoperating the machine with the blades directly on the concrete surface.

The method may also include hand finishing of the concrete surface 228.For example, as shown in FIGS. 12 and 13 , placing or finishingpersonnel may trowel the surface of the concrete with hand trowels 110.In one or more examples, personnel may use kneeling boards 126 to spreadthe personnel load on the concrete 54 to reduce and/or avoid creatingdepressions in the surface of the concrete. The hand trowels 110 mayinclude handheld steel , wood, plastic, or other material blades thatmay further smooth out the surface of the concrete by bringing furthercementitious butter to the surface. A relatively smooth and/or shinysurface may be created using the hand trowels and narrower or harder toaccess areas may also be addressed using the hand trowels. That is, forexample, as shown in FIG. 13 , a power float or trowel may be unable toaccess the concrete surface between the pipe stubs, and hand finishingtools may be used to finish the concrete in those areas.

During or after the machine finishing process above and/or during orafter the hand finishing process above, but before substantial settingof the concrete, the method may include repeating several of theprocesses 230 described above. That is, for example, the steps ofcapturing a surface profile, generating a surface profile depiction,displaying the depiction, and informing placement and/or finishingpersonnel, and remediating high/low areas may be repeated. However, thetolerance used at this stage of the process may be slightly lower ortighter, as described above. As shown in FIG. 14 , the variance in thehigh/low regions may be reduced (e.g., A/B as compared to A-C) and thesurface depiction 122C may begin to look more uniform and/or with fewerregions that vary from the desired surface elevation.

The method may also include verifying the floor flatness 232. That is,as shown in FIG. 16 , floor flatness may be verified or determined basedon a 120 inch or 10 foot long straight edge. As shown in FIG. 15 ,various floor flatness (FF) numbers after the final finishing steps maybe defined by the variance of the floor surface within the 120 inchdistance. That is, as shown, an FF number of 20.2 may be defined by afloor surface that varies no more than an ⅛ inch every 30 inches.Similarly, an FF number of 27.9 may be defined by a floor surface thatvaries no more than ⅛ inch every 40 inches. Still further an FF numberof 52.9 may be defined by a floor surface that varies no more than ⅛inch every 60 inches and an FF number of 191.4 may be defined by a floorsurface that varies no more than ⅛ inch in the full 120 inches. Other FFnumbers may be defined by different gap dimensions (e.g., 3/16 inch,5/16 inch, or ½ inch) as shown in FIG. 15 . In view of the above andwith reference to FIG. 16 , a 120 inch straight edge may be used toinspect the slab surface at a series of locations and determine a floorflatness number. The inspection may be performed to confirm compliancewith an architectural specification, for example. That is, an architectmay specify a floor flatness and/or may specify a floor flatness and aminimum floor flatness. In the latter case, the specified floor flatnessmay be an average floor flatness and any particular floor flatnessreading may be required to be above the minimum. In one or moreexamples, an architect may specify floor flatness values in particularareas, on particular levels of a building, or may otherwise define thearea subject to the floor flatness specification. In view of the above,a concrete slab may include an entire level of a building or aparticular area or zone of a level of a building, which may include oneor more concrete pours. Alternatively, a concrete slab may include theextent of a particular pour, for example. Still other boundaries may beused to define a concrete slab.

The above system and/or performance of the above method may result inmarked improvements in floor flatness, particularly on elevated slabs.That is, heretofore, systems for ongoing monitoring of concrete slabplacement and finishing may have involved spot checking during thefinishing processes. These spot-checking approaches may be subject todeflections in the formwork, when the spot checks are based on concretethickness. Moreover, these spot checks, by their very nature, do notaccount for variations in the surface of the concrete at other locations(e.g., between the spots). As such, floor flatness during the placingand finishing process was subject to large variations in flatness thatwere not observable by the naked eye and, as such, often went entirelyunnoticed and not detected until after the concrete was substantiallyset and floor flatness inspections were performed. With the presentsystem, particular problematic areas such as areas around pipepenetrations as shown in FIG. 13 , slab edges beyond column lines asshown in FIG. 17 , as well as the entirety of the slab surface mayquickly be assessed on an ongoing basis using the surface sensor and theassociated surface profile depiction. This ongoing and complete orsubstantially complete surface assessment during the concrete placingand finishing process allows for floor flatness values to be achievedthat were once thought not possible or practical. As such, much time andcost can be saved by avoiding the need for remediation of the slab afterthe concrete is substantially set. Moreover, the surface appearance ofthe concrete may be more uniform by avoiding grinding of high areasand/or leveling or filling of low areas. Where exposed concrete isdesired, this is particularly game changing.

Regarding exposed or polished concrete, reference is made to FIG. 18 .As shown, the aggregate within the concrete 54 may be generally evenlydispersed throughout the concrete and the rounded edges of the aggregatenear the surface may be arranged generally tangentially with thesurface. If a slab is poured as shown with an FF number of approximately25 (e.g., as opposed to something closer to 35 or 50), floor grindingand/or filling may be performed to achieve the desired floor flatness.However, as shown in FIG. 18 , this will cause further exposure of theaggregate in the high areas by grinding down to areas where thecross-section of the aggregate is larger, but in lower areas, theaggregate exposure may be relatively unchanged. As shown in FIG. 19 ,this can result in a non-uniform appearance on the surface of theconcrete. In contrast, if the floor flatness of 35 or 50 is achievedfrom the outset by monitoring the placement and finishing of theconcrete as described herein, floor grinding and filling may be avoidedand a more uniform appearance of the concrete may be provided as shownin FIG. 20 .

It is to be appreciated that concrete curing is a time sensitive processand that properties of cured concrete may often be determined at timeframes such as 7 days and 28 days. In contrast, concrete setting canbegin as soon as the concrete is mixed and/or as soon as the concrete isplaced, for example. That is, as shown in FIGS. 11-13 , the concrete mayset sufficiently to support machine finishing equipment and workers arelatively short time after the concrete is placed. The presentapplication contemplates performing the surface capture information andrelated depiction generation, display, informing personnel, andremediation steps before substantial and/or full setting or firming ofthe concrete which may be defined by a period of time suitable forfinishing of the concrete surface. For example, concrete finishing mayoccur over a period of hours after concrete placement such as afinishing window of 0-12 hours, or from 0-8 hours, or from 0-4 hours, orfrom 0-2 hours, or from 0-1 hour, for example. As such, where referenceto finishing or remediation operations are discussed herein that areprior to substantial setting, these operations should be considered tobe performed within a suitable concrete finishing window described.

It is further to be appreciated that while depictions 122A, 122B, and122C have been shown herein, these depictions are different only to theextent the slab profile is different. That is, any number of depictionsmay be generated throughout the process and should not be limited to thethree depictions mentioned. Moreover, while depictions were suggested asbeing generated after initial formation of the concrete surface, afterfurther finishing, and after machine or hand finishing, additional orfewer depictions may be used and the repeating of the related steps maybe performed accordingly. Moreover, in one or more examples, where aparticular depiction shows that all areas fall within a particulartolerance, steps to inform and remedy the issues may be skipped. Stillother steps may be skipped, repeated, and/or reordered as desired by theuser.

As used herein, the terms “substantially” or “generally” refer to thecomplete or nearly complete extent or degree of an action,characteristic, property, state, structure, item, or result. Forexample, an object that is “substantially” or “generally” enclosed wouldmean that the object is either completely enclosed or nearly completelyenclosed. The exact allowable degree of deviation from absolutecompleteness may in some cases depend on the specific context. However,generally speaking, the nearness of completion will be so as to havegenerally the same overall result as if absolute and total completionwere obtained. The use of “substantially” or “generally” is equallyapplicable when used in a negative connotation to refer to the completeor near complete lack of an action, characteristic, property, state,structure, item, or result. For example, an element, combination,embodiment, or composition that is “substantially free of” or “generallyfree of” an element may still actually contain such element as long asthere is generally no significant effect thereof.

To aid the Patent Office and any readers of any patent issued on thisapplication in interpreting the claims appended hereto, applicants wishto note that they do not intend any of the appended claims or claimelements to invoke 35 U.S.C. § 112(f) unless the words “means for” or“step for” are explicitly used in the particular claim.

Additionally, as used herein, the phrase “at least one of [X] and [Y],”where X and Y are different components that may be included in anembodiment of the present disclosure, means that the embodiment couldinclude component X without component Y, the embodiment could includethe component Y without component X, or the embodiment could includeboth components X and Y. Similarly, when used with respect to three ormore components, such as “at least one of [X], [Y], and [Z],” the phrasemeans that the embodiment could include any one of the three or morecomponents, any combination or sub-combination of any of the components,or all of the components.

In the foregoing description various embodiments of the presentdisclosure have been presented for the purpose of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise form disclosed. Obvious modifications orvariations are possible in light of the above teachings. The variousembodiments were chosen and described to provide the best illustrationof the principals of the disclosure and their practical application, andto enable one of ordinary skill in the art to utilize the variousembodiments with various modifications as are suited to the particularuse contemplated. All such modifications and variations are within thescope of the present disclosure as determined by the appended claimswhen interpreted in accordance with the breadth they are fairly,legally, and equitably entitled.

What is claimed is:
 1. A concrete finishing system, comprising: asurface sensor configured to capture surface profile data of a concretesurface, the surface sensor being arranged such that a concrete workarea where concrete is being finished is within a field of view of thesurface sensor; a depiction generator configured to generate a depictionof a surface profile of the concrete showing variation in the flatnessof the concrete surface; and a display configured to display thedepiction.
 2. The concrete finishing system of claim 1, wherein thedepiction includes a three-dimensional depiction suitable for atwo-dimensional display.
 3. The concrete finishing system of claim 2,wherein the three-dimensional depiction includes a heat map.
 4. Theconcrete finishing system of claim 3, wherein the three-dimensionaldepiction includes a contour map.
 5. The concrete finishing system ofclaim 1, wherein the depiction generator is configured to display pointvalues showing an elevation variance from flat at a particular point. 6.A method of finishing concrete, comprising: arranging a surface sensorsuch that a work area for placement of the concrete is within a field ofview of the surface sensor; capturing surface profile data of a surfaceof the concrete during placement or finishing of the concrete;generating a surface profile depiction based on the surface profiledata; displaying the surface profile depiction; and informing personnelregarding a variation in height based on the depiction.
 7. The method ofclaim 6, wherein capturing surface profile data comprises capturingsurface profile data after placement of the concrete and before furtherfinishing of the concrete.
 8. The method of claim 7, wherein capturingsurface profile data comprises capturing surface profile data afterinitial forming of the concrete surface and before further finishing. 9.The method of claim 8, wherein initial finishing comprises striking offthe concrete or finishing the concrete with a bull float and furtherfinishing comprises finishing the concrete with a highway straight edge.10. The method of claim 7, further comprising instructing remediation ofhigh or low areas that are more than ½ inch high or ½ inch low.
 11. Themethod of claim 7, wherein capturing surface profile data furthercomprises capturing surface profile data after further finishing of theconcrete and before machine finishing and hand finishing of theconcrete.
 12. The method of claim 11, wherein further finishingcomprises finishing the concrete with a highway straight edge.
 13. Themethod of claim 11, further comprising instructing remediation of highor low areas that are more than ¼ inch high or ¼ inch low.
 14. Themethod of claim 11, wherein capturing surface profile data furthercomprises capturing surface profile data after machine finishing of theconcrete and before substantial setting of the concrete.
 15. The methodof claim 14, wherein machine finishing comprises finishing the concretewith a power float or trowel.
 16. The method of claim 14, furthercomprising instructing remediation of high or low areas that are morethan ⅛ inch high or ⅛ inch low.
 17. A concrete slab having a floorflatness value above 25 and comprising a surface free of ground areasand free of filled areas, the slab being formed by a method comprising:arranging a surface sensor such that a work area for placement of theconcrete slab is within a field of view of the surface sensor; capturingsurface profile data of a surface of the concrete slab during placementor finishing of the concrete; generating a surface profile depictionbased on the surface profile data; displaying the surface profiledepiction; and informing personnel regarding a variation in height basedon the depiction.
 18. The concrete slab of claim 17, wherein capturingsurface profile data comprises capturing surface profile data afterplacement of the concrete slab and before further finishing of theconcrete slab.
 19. The concrete slab of claim 18, wherein capturingsurface profile data further comprises capturing surface profile dataafter further finishing of the concrete slab and before machinefinishing and hand finishing of the concrete slab.
 20. The concrete slabof claim 19, wherein capturing surface profile data further comprisescapturing surface profile data after machine finishing of the concreteslab and before substantial setting of the concrete slab.